Posted by larrylohrman on November 19, 2007
This post has nothing to do with B17s except that I’ve used some images from my B17 360VR series as examples in this tutorial.
I get a bunch of questions on how I create full screen Flash panoramas and how to put a number of 360 views together into a tour so for a long while I’ve been working on a tutorial on making full screen panoramas and an HTML template with instructions on how to make a multi-view tour.
In the tutorial I explain how to download the the HTML for this template and turn it into your own tour. This HTML may look a little “scary” to someone who’s not used to hacking HTML but you don’t have to understand what it’s doing unless you want to make significant changes. All you need to make your own tour from this template is a text editor, a place on the web you can FTP to and a FTP application.
Have, fun and let us all know about improvements you make to this template. The basic design of this template is thanks to some collaboration I did with Ted Barrow of Fort Worth, TX. He suggested some rearrangements of the tour design that I started out with.
Posted in Panoramas, Virtual Tours | 6 Comments »
Posted by larrylohrman on November 16, 2007
I’d like to comment and elaborate on a discussion thread that is going on in the Photography For Real Estate flickr group. I’ve noticed quite a number of folks using stitched images for real estate photos.First I need to admit that when I first discovered stitching I used an image of a large master bedroom on a flyer layout. My wife (my Realtor client) and the seller both went ballistic about the curved lines. I recall not agreeing with my clients on this criticism at the time because I was fascinated by the technology of stitching. I thought this was a wonderful way to show this large room but I changed my flyer to use rectilinear images.The example image above is six images (shot with a Canon 10-22 mm lens on a Canon 20D) stitched together with the photomerge feature of Photoshop CS3 (fantastic stitching software by the way). I think the image above is a wonderful image except for the fact that the lines of the windows are curved. These curved lines create a very similar distraction that barrel distortion causes. That is, you know very well that it is unlikely that this wall is curved yet the wall is curved is curved in the photo. It’s a visual contradiction that grabs the viewers attention and distracts from the real purpose of the photo; not what you want in a marketing photo.The reason the lines are curved is that this image is a cylindrical projection of the 3D space of this room onto a 2D surface. Photomerge will try make a rectilinear projection if you use the “perspective” option. However, if you try to make a rectilinear projection of an image that has a field of view (FOV) wider than 120 degrees the perspective gets wildly distorted and the distortion is all on the left and right edges. For more interesting reading and examples on the subject of cylindrical vs rectilinear projections see this article. The conclusion of this article is:
“deformation is evenly distributed in a cylindrical panorama while it’s concentrated near image sides when rectilinear mode is used. 360° is possible when using cylindrical projection. 90° to 120° is acceptable (depending on the subject) when using rectilinear projection.”
Interestingly this straight line problem with using cylindrical panoramas for interiors almost never happens when you use them for landscapes. That’s because your eye usually can’t even spot straight lines being rendered as curves if there aren’t long straight lines.The bottom line on using stitched images for interiors or exteriors with long straight lines is that if you use them, use rectilinear stitching and keep the horizontal field of view less than 120 degrees and probably closer to 100 degrees so the perspective distortion on the left and right side of the image is not too objectionable.
Nov 18 Update: I want to point out the excellent comment below that Jon May made today. It points out a article by Georges Lagarde and a photo in Jon’s flickr photo stream where Jon has used the technique described by Lagarde. In short, what this means is there are in fact techniques to “fix” the perspective distortions I described above and the seventeenth century venetian masters understood and used these techniques. These non-classical perspective “tricks” that the venetian masters used can be used for photographic images.
This is what I love about this medium (collaborative Internet discussions). When you carry on a global discussion like we are here you end up with far than you would in any other form of interaction! Thanks Jon for this insight!
Posted in Panoramas | 8 Comments »
Posted by larrylohrman on July 16, 2007
I’ve had several questions recently about making 360 panoramas so I thought I’d visit this subject again.
There are some that think that the work it takes to do 360s is not worth it and there are many that think having a 360 tour can set your real estate marketing apart from the crowd. I’ve done 360s for many years and make it a point to talk to buyers and sellers to see if they’ve seen the 360s and ask them what they think. I’ll have to say that not everyone appreciates 360s and some plain don’t like them.
On the positive side we sold one home a few years ago in a very fast market where some out of town buyers saw only the 360s and stills before signing a contract. They, saw the stills and knew I was making 360s and waited till I posted them to sign the deal. The first time they saw the physical house was at the inspection. This is the home. These 360s were done back when I was using only QuickTime. The buyers were moving from California to Issaquah and had made offers on and lost 6 different homes before this one. Their belongings were on a moving truck… they were clearly under unusual pressure.
This clearly is an unusual situation for a home sale yet we repeatedly rent our furnished rental based only on the 360s. This happens about 30% of the time. So, there is good evidence that the full screen 360s that I use are effective.
I believe that now that most of the real estate buying world has high speed internet access, large full screen 360s set the marketing apart much more than little tiny 360s. Notice the level of detail of a room that can be seen in a full screen 360. So much detail that it’s relatively difficult to control all the defects. Note you have to click on the X on the left-hand lower control bar to make this image go to full screen. This full screen 360 is done with Flash and demands that Flash version 9 be loaded on your machine to display the image. Flash 9 has new graphic features that make the display of full screen 360 spherical images practical. This chart shows that as of this date Flash 9 is installed on about 83% of machines so no download/install is required.
I’ve started to use only Flash for full screen real estate 360s. QuickTime is still some what smoother panning than the Immervision Flash Player that I use but not enough to risk have buyers needing to download and install Quicktime which is pretty big and ugly on Windows machines. Java is a pretty big download too and currently has about the same penetration as Flash 9.
The question that got me going on this post was about the 360 One VR which is a parabolic mirror that reflects a 360 image on one frame. This device is certainly quick and easy but the quality of the image it creates is low so you can’t easily make large 360 images. To me tiny little 360s were interesting 10 years ago but are yawners these days.
So how do you make full screen 360s? I have to apologize to those readers I’ve promised to finish my tutorial on how to shoot full screen 360s. I promise to finish it soon. To summarize briefly you need a fisheye lens and a panoramic head. The Nikon 10.5 is very popular (works on Canon too) or the Sigma 8mm is OK but not as high quality as the Nikon 10.5. The panoramic head allows you to take 3 to 6 shots rotated around the lenses aperture plane in a perfectly level swing so the stitching works well. The images are stitched together with stitching software (PTgui is may favorite) and then posted to the web with some HTML and player software.
The bottom line is that 360 VR is allot of work, requires added equipment and some practice to get it done right and quickly. The question is, is it worth the extra work and expense? It’s hard to tell for sure. Some buyers and sellers (usually the more geeky ones) think it’s fantastic while others don’t even get what its all about. I do it for all our listings mainly because I enjoy doing it and do it for other subjects than real estate… my non-real estate 360vr images are at www.fullscreen360.blogspot.com.
Posted in Panoramas, Virtual Tours | 30 Comments »
Posted by larrylohrman on April 28, 2007
Wow, the new photomerge feature in Photoshop CS3 is a huge improvement compared to previous versions of photomerge. The idea of photomerge is to stitch together a series of photos into a panorama similar to the panorama above. I made this panorama from six overlapping shots that cover about 180 degrees of horizontal view. The six shots were taken without a tripod and in aperture priority mode. Normally you would use a tripod to make sure the shots line up nicely for stitching and use manual exposure mode so all parts of the panorama had the same exposure. But I wanted to test the stitching, alignment and blending algorithms in photomerge.
This second panorama is made from the very same six photos with the older photomerge that is in Photoshop Elements 5.0. I think the same photomerge is in Photoshop CS2 and earlier versions.
Notice the nice blending job that the new photomerge (top most example) did when the shutter speed was increased towards the right side of the panorama that was towards the sun. You have to look closely to in the top example to that there is a change in exposure on the right-hand side. The old photomerge makes kind of a mess and doesn’t even try to blend the different images.
A panoramic shot can be nice on a property brochure or flyer or a web site. Many do-it-yourself virtual tour sites allow you to use this kind of panorama shot. In the past I’ve always used specialized stitching software like PhotoVista or PTgui to make panoramas because Photoshop did such a bad job. Photoshop CS3 has changed that, photomerge finally stitches and blends panoramas as good or better than specialized software.
BTW, if you want to get some more in depth how-to on using Photomerge in CS3 there is a multi-part Video podcast on this subject currently at lynda.com. All you need is a free download of Apple iTunes. After installing iTunes, use iTunes to subscribe to the lynda.com podcast. You can then watch the video on either your PC/MAC or iPod. The Photomerge podcast is #59 for April 20.
Posted in Panoramas, Photo Editing | 2 Comments »
Posted by larrylohrman on March 13, 2007
I’ve been having an interesting discussion with my friend Kevin Caskey about HDR (High Dynamic Range) processing of spherical panoramas. Kevin is a photographic savvy Realtor in Bellevue, WA that shoots his own spherical panoramas. Kevin discovered and pointed out Photomatix software to me. He showed me his QuickTime VR panorama of his living room that he processed created with Photomatrix.
The typical problem encountered when shooting panoramas is that since you have to shoot all shots being stitched together at the same exposure settings so that you can stitch them together so you have a hard time dealing with scenes that have an extreme dynamic range.
Here’s some background on HDR and Photomatix. The way HDR works is that in addition to the normal exposure you take one or more exposures with less exposure and one or more exposures with more exposure than the normally exposed image. You then combine the multiple images together in a way that takes the “best” parts of each image and results in an image that has a dynamic range of all the combined images. This combining process is what Photomatix does.
Why would you want to go to the work of taking multiple images and combining them? For interiors, it’s an alternative to artificial lighting. For outdoor shots it’s the only way to get the shot if you are faced with a wide range of brightness.
So Kevin used HDR processing with Photomatrix on this QuickTime VR shot of his living room. To appreciate this use of HDR, compare it with this panorama which is some of the same files from Kevin’s panorama only without HDR processing. This second shot is just one shot in each of 3 directions stitched together. Whereas Kevin’s shot is 3 shots in each of 3 directions and all 3 images in each direction combined with Photomatix and the final 3 HDR image stitched toghether. In comparing the two panoramas you will quickly see that Kevin’s HDR panorama has more even lighting around the whole 360 view much like you would get if you’d used a flash unit. In the non-HDR version of the panorama the lighting is more uneven around the 360 degrees of view. The windows are well exposed but the opposite direction is quite underexposed.
When working inside I’d rather use a external flash unit and take one shot in each direction since it’s a lot less processing work than using Photomatix and shooting 3 times more images. However, when you are shooting outside where you can’t can’t control the lighting there is no other way of capturing the total brightness range of a scene with a bright sky and not so bright foreground.
Last April I did a post on some ways to do image blending for interiors as an alternative to using lighting equipment. Photomatix is another piece of software that goes works in a similar way to the techniques I described in that post. However, with Photomatix you have much more control over the combining of images with a process that’s called “tone-mapping”. For a complete tutorial on HDR and using Photomatrix see www.naturescapes.net.
Posted in Panoramas, Photo Editing, Virtual Tours | 14 Comments »
Posted by larrylohrman on May 10, 2006
More news from Tabb at nwaerialphotography.com. Tabb has now well on his way to perfecting the process of creating spherical panoramas for his Helicam. Tabb sent me this example shot today. Tabb uses a Canon 5D suspended under the Helicam with a Canon 15mm wide angle lens. The Canon 15mm lens is produces a really crisp, sharp image. Tabb says this particular QuickTime VR image was stitched from 24 shots with PTgui. Anyone who has stitched handheld panoramas can appreciate the difficulty of producing this kind of image from a Helicam! Great job Tabb!
Posted in Panoramas, Photo Technique | 3 Comments »
Posted by larrylohrman on April 25, 2006
I’ve been talking to a number of people in the last few months about their use of virtual tours. I’ve also been trying to decide what the next step should be for the virtual tours that I create myself.
The conclusion I’ve come to is that virtual tours are an opportunity to use full screen images and to go above and beyond what’s available on MLS sites and all the public real estate sites. There are all kinds of technology available for the web that can go beyond the small photos and relatively mundane marketing that is used by most sites. Of all the virtual tours I’ve experimented with in the last few years the most popular with buyers and sellers by far are full screen spherical (also called cubic) QuickTime panoramas. There is nothing like floating in the center of a room and looking in any direction you want.
There are currently three technologies that allow presentation of full screen immersive spherical images:
- QuickTime VR by Apple
- SPI-V by Aldo Hoeben which is based on Shockwave
- ImmerVision by the company of the same name based on JAVA
There are downsides to each one of these technologies based on the fact that not all PCs have the required software installed and the relative difficulties of users downloading what they need to view the spherical panoramas. However, there are enough people with the required software that I think it is well worth using full screen spherical panoramas.
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Posted by larrylohrman on April 15, 2006
Today a reader posed an interesting question. “…isn’t a panorama a replacement for a wide-angle lens without the problem of perspective exaggeration you get with ultra-wide angle lenses?”
I’ve never thought of it in those terms but yes it is. A couple of fames stitched together will in fact increase your horizontal field of view (HFOV). The key is that it needs be very fast and easy to stitch the frames together for this approach to make sense.
The concept of fast and easy panorama stitching got me thinking. There are cameras on the market now that have features that aid in shooting panoramas and some actually stitch the panorama in the camera.
Camera assists shooting panoramas
These lists are probably not a complete, these are the ones I found in the first 5 pages of a Google search for “in camera stitching”.
Thanks Eric in California for getting me thinking about panoramas in this light.
Posted in Panoramas, Photo Equipment | 1 Comment »
Posted by larrylohrman on April 14, 2006
My last post on panoramas barely scratched the surface. I think this is a very important subject for real estate photographers since the use of panoramas is a very effective method of showing more of small spaces that is possible with traditional single frame photography. I’ve started a resource page with links to more information on this subject. If you are interested in the subject of panoramas I suggest that you look through some of the tutorials on panoguide.com. These are just a few of my favorite links. I’ll be expanding this list in the future.
Jook Leung’s work has been a great inspiration to me in the area of VR panoramas. Jook is professional Photographer and Illustrator that works out of New York and is a master in the area of creating full screen QuickTime VR panoramas.
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Posted by larrylohrman on April 12, 2006
An essential tool for real estate photography is the panorama. A panorama is just a photograph with an extra wide view. Panoramas can be just two contiguous photos like the example above or many more shots that make a complete 360 degree view. The example above is two shots with a 35mm lens stitched together with Photovista 3.0 to illustrate the view from a home we sold on Cougar Mountain. This view was just under 180 degrees and a single photo just did not show off the full view.
Panoramas like this are easy to shoot. It helps to use a tripod to keep the camera level from shot to shot but it is not essential. You need to have an overlap of about 30% from shot to shot so its easy to match up the images during stitching. The other thing you need to do is to put you camera in manual mode so none of camera settings change from shot to shot. Shooting all the shots in the panorama with the same exposure, zoom and auto focus settings will make sure the shots being stitched together nicely fit together in one smooth image.
I’ve tried a lot of stitching software including using Photoshop and Photoshop Elements but of all the stitching software I’ve used I think the fastest and easiest way to stitch this kind of panorama is with Photovista 3.0. All Photovista needs to know is what the focal length of the lens is and what the order of the photos is and it does everything else. And the results are usually flawless.
Panoramas are great for showing off a view property. They work very well using anywhere from a very wide-angle lens (15mm) to medium telephoto lenses (200mm) depending on the view. They also are frequently used for interiors. The problem with using cylindrical panoramas (photos projected on the inside of a cylinder) for interiors is it is always a struggle to get enough vertical field of view for interiors with one horizontal series of images. To increase the field of view you can use a panoramic head to shoot multiple rows of photos or the way I do it is to use a fisheye lens and create spherical or cubic panoramas. But using a fisheye lens requires special stitching software and techniques. More on this subject in some other post. Start out shooting a simple contiguous set of images like the one above.
Many virtual tour providers provide Java, Flash or QuickTime viewers that automatically handle rotation of 180 degree or 360 degree panoramas. Panoramas of up to 180 degrees work very nicely in print media on flyers and brochures.
Posted in Panoramas | 1 Comment »
Posted by larrylohrman on February 16, 2006
I received a reader question about what setup I use for 360 photos. I use a Canon 1Ds with a Sigma 8mm fisheye lens and a simple homemade bracket for my tripod that mounts the camera so it rotates around the entrance pupil of the lens and has a bubble level to keep the camera level in two planes while rotating. When shooting a 360 photo this setup allows me to quickly shoot 4 fisheye images that can be stitched together to create a complete spherical image. Click here for a more detailed example. I use PTGui to stitch the 4 fisheye images together. Using this setup the shooting time is about 30 to 45 seconds per 360 image. When I'm not shooting the interior of a home I don't bother with the tripod so I can do 360 steet images etc without dragging around a tripod. I love to shot street 360 images this way.
I put 5 to 10 – 360 photos together to form a virtual tour for a home that looks like this. I host the 360 photos in two formats: FlashVR is the format you see initially. This is a Flash based format that 90+ percent of visitors can immediately see. Since these Flash tours are not the highest quality possible I also provide a link to a QuickTime tour of the same images for those viewers that either have QuickTime installed or are willing to install it to see the tour.
Posted in Panoramas, Photo Technique | 2 Comments »